Epidemiological investigation and phylogenetic analysis of Toxoplasma gondii strains from animal and human hosts as evidence of zoonotic spread in Duhok, Iraq
Keywords:
Toxoplasma gondii, ITS1 rDNA sequencing, Phylogenetic clustering, Cross-species transmission, One Health approachAbstract
This study aimed to investigate the genetic diversity and transmission dynamics of Toxoplasma gondii strains isolated from animals and humans in Duhok Governorate, Iraq. A total of 15 strains originating from chickens, horses, sheep, and women with a history of abortion were analyzed using PCR amplification and sequencing of the ITS1 rDNA region. Phylogenetic analysis revealed all local strains clustered into a single, well-supported monophyletic clade, regardless of host species or geographic location, indicating a common ancestral origin. In contrast, global reference strains showed marked genetic divergence and did not cluster with the Duhok isolates. Although most Duhok strains appeared generalist, minor host-associated sub-clustering and unique branching patterns were observed. These findings underscore the importance of region-specific control strategies, including improved sanitation, safer animal management, and public education. The study advocates for a “One Health” approach, integrating human, veterinary, and environmental health efforts to monitor and mitigate the spread of T. gondii in endemic areas.
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